A voice transmitter for a breathing protective mask is disclosed in European patent publication 0,413,861. The voice transmitter disclosed in this publication includes two housing components between which a voice membrane is clamped. The pretensioning of the voice membrane is necessary for a good voice transmission and is achieved with interengaging cylindrical and inclined surfaces. The two housing components are held together by a snap mechanism. The known voice transmitter can be assembled in a simple manner but it is no longer possible to subsequently change the voice membrane tension. This causes a large range of variation of the voice transmitting characteristics.